The present invention relates to an optical film reader for reading information contained on film strips and more particularly to a manually operated optical film reader for projecting and enlarging microcopy information recorded in rollfiche format on rolls of photographic film.
In recent years the rapid increase in the production of written information has resulted in the concomitant problem of efficient information storage and retrieval. In order to reduce the physical volume of documents and other printed material that must be stored and made available for rapid retrieval and inspection, microfilm techniques in which documents, data and other printed matter are photographed in a reduced size have become common. Microfilm containing such information allows for a convenience in storage and transportation as many thousands of printed pages can be contained on a single roll of film. Another attendant advantage of such microfilm techniques is that enlarged prints can be made from the film, or the film can be viewed by projection on a screen or viewer.
In addition to roll microfilm recording of information, microfiche, a sheet of microfilm approximately 4 inches by 6 inches is also used to record microcopy. A single microfiche can contain many pages of microcopy and has an advantage over conventional roll microfilm in that recorded information can be readily indexed with respect to a two coordinate system; along the margins of the fiche or microfilm sheet. Thus information can be rapidly located upon reference to the particular address or horizontal and vertical coordinates of the information when the sheet is placed in a microfiche projection device and viewed.
In order for the information recorded on microfilm or microfiche to be viewed, or enlarged prints obtained the film or fiche must be projected in a viewer or reader. A major disadvantage of prior art viewers and projectors is that they have been expensive, bulky and often complicated to operate. Prior art viewers and readers have required the operator to handle the film or microfiche subjecting it to dust, moisture, scratching of the film and other hazards of mishandling such as misfiling or theft. Another disadvantage of microfilm and microfiche systems found in the prior art is that multiple rolls of microfilm or many individual sheets of microfiche are required to store large quantities of information.